diff --git a/file.go b/file.go
index 386a18d..97442c5 100644
--- a/file.go
+++ b/file.go
@@ -85,10 +85,42 @@ func (f FileFilters) apply(o *options) {
 	o.fileFilters = append(o.fileFilters, f...)
 }
 
-// macOS filters by case insensitive literal extension.
-// Extract all literal extensions from all patterns.
-// If those contain wildcards, or classes with more than one character, accept anything.
-func (f FileFilters) darwin() []string {
+// Windows' patterns are case insensitive, don't support character classes or escaping.
+// First we remove character classes, then escaping. Patterns with literal wildcards are invalid (match nothing).
+// The semicolon is a separator, so we replace it with the single character wildcard.
+func (f FileFilters) simplify() {
+	for _, filter := range f {
+		for i, pattern := range filter.Patterns {
+			var escape, invalid bool
+			var buf strings.Builder
+			for _, r := range removeClasses(pattern) {
+				if !escape && r == '\\' {
+					escape = true
+					continue
+				}
+				if escape && (r == '*' || r == '?') {
+					invalid = true
+					break
+				}
+				if r == ';' {
+					r = '?'
+				}
+				buf.WriteRune(r)
+				escape = false
+			}
+			if invalid {
+				filter.Patterns[i] = ""
+			} else {
+				filter.Patterns[i] = buf.String()
+			}
+		}
+	}
+}
+
+// macOS filters by "type"; the case insensitive literal extension is a good proxy.
+// So we extract the extension from each pattern, remove character classes, then escaping.
+// If an extension contains a wildcard, any type is accepted.
+func (f FileFilters) types() []string {
 	var res []string
 	for _, filter := range f {
 		for _, pattern := range filter.Patterns {
@@ -114,6 +146,9 @@ func (f FileFilters) darwin() []string {
 	return res
 }
 
+// Remove character classes from pattern, assuming case insensitivity.
+// Classes of one character (case insensitive) are replaced by the character.
+// Others are replaced by the single character wildcard.
 func removeClasses(pattern string) string {
 	var res strings.Builder
 	for {
diff --git a/file_darwin.go b/file_darwin.go
index 9023358..dc73507 100644
--- a/file_darwin.go
+++ b/file_darwin.go
@@ -14,7 +14,7 @@ func selectFile(opts options) (string, error) {
 		data.Operation = "chooseFolder"
 	} else {
 		data.Operation = "chooseFile"
-		data.Options.Type = opts.fileFilters.darwin()
+		data.Options.Type = opts.fileFilters.types()
 	}
 
 	out, err := zenutil.Run(opts.ctx, "file", data)
@@ -34,7 +34,7 @@ func selectFileMutiple(opts options) ([]string, error) {
 		data.Operation = "chooseFolder"
 	} else {
 		data.Operation = "chooseFile"
-		data.Options.Type = opts.fileFilters.darwin()
+		data.Options.Type = opts.fileFilters.types()
 	}
 
 	out, err := zenutil.Run(opts.ctx, "file", data)
diff --git a/file_filter_test.go b/file_filter_test.go
index 55c525c..cdd5786 100644
--- a/file_filter_test.go
+++ b/file_filter_test.go
@@ -5,27 +5,55 @@ import (
 	"testing"
 )
 
-func TestFileFilters_darwin(t *testing.T) {
+func TestFileFilters_simplify(t *testing.T) {
 	tests := []struct {
 		data FileFilters
 		want []string
 	}{
-		{FileFilters{{"", []string{`*.png`}}}, []string{`png`}},
-		{FileFilters{{"", []string{`*.pn?`}}}, nil},
-		{FileFilters{{"", []string{`*.pn\?`}}}, []string{`pn?`}},
-		{FileFilters{{"", []string{`*.[PpNnGg]`}}}, nil},
-		{FileFilters{{"", []string{`*.[Pp][Nn][Gg]`}}}, []string{`PNG`}},
-		{FileFilters{{"", []string{`*.[Pp][\Nn][G\g]`}}}, []string{`PNG`}},
-		{FileFilters{{"", []string{`*.[PNG`}}}, []string{`[PNG`}},
-		{FileFilters{{"", []string{`*.]PNG`}}}, []string{`]PNG`}},
-		{FileFilters{{"", []string{`*.[[]PNG`}}}, []string{`[PNG`}},
-		{FileFilters{{"", []string{`*.[]]PNG`}}}, []string{`]PNG`}},
-		{FileFilters{{"", []string{`*.[\[]PNG`}}}, []string{`[PNG`}},
-		{FileFilters{{"", []string{`*.[\]]PNG`}}}, []string{`]PNG`}},
+		{FileFilters{{"", []string{`*.png`}}}, []string{"*.png"}},
+		{FileFilters{{"", []string{`*.pn?`}}}, []string{"*.pn?"}},
+		{FileFilters{{"", []string{`*.pn;`}}}, []string{"*.pn?"}},
+		{FileFilters{{"", []string{`*.pn\?`}}}, []string{""}},
+		{FileFilters{{"", []string{`*.[PpNnGg]`}}}, []string{"*.?"}},
+		{FileFilters{{"", []string{`*.[Pp][Nn][Gg]`}}}, []string{"*.PNG"}},
+		{FileFilters{{"", []string{`*.[Pp][\Nn][G\g]`}}}, []string{"*.PNG"}},
+		{FileFilters{{"", []string{`*.[PNG`}}}, []string{"*.[PNG"}},
+		{FileFilters{{"", []string{`*.]PNG`}}}, []string{"*.]PNG"}},
+		{FileFilters{{"", []string{`*.[[]PNG`}}}, []string{"*.[PNG"}},
+		{FileFilters{{"", []string{`*.[]]PNG`}}}, []string{"*.]PNG"}},
+		{FileFilters{{"", []string{`*.[\[]PNG`}}}, []string{"*.[PNG"}},
+		{FileFilters{{"", []string{`*.[\]]PNG`}}}, []string{"*.]PNG"}},
 	}
-	for _, tt := range tests {
-		if got := tt.data.darwin(); !reflect.DeepEqual(got, tt.want) {
-			t.Fatalf("FileFilters.darwin(%+v) = %v, want %v", tt.data, got, tt.want)
+	for i, tt := range tests {
+		tt.data.simplify()
+		if got := tt.data[0].Patterns; !reflect.DeepEqual(got, tt.want) {
+			t.Errorf("FileFilters.simplify[%d] = %q, want %q", i, got, tt.want)
+		}
+	}
+}
+
+func TestFileFilters_types(t *testing.T) {
+	tests := []struct {
+		data FileFilters
+		want []string
+	}{
+		{FileFilters{{"", []string{`*.png`}}}, []string{"png"}},
+		{FileFilters{{"", []string{`*.pn?`}}}, nil},
+		{FileFilters{{"", []string{`*.pn;`}}}, []string{"pn;"}},
+		{FileFilters{{"", []string{`*.pn\?`}}}, []string{"pn?"}},
+		{FileFilters{{"", []string{`*.[PpNnGg]`}}}, nil},
+		{FileFilters{{"", []string{`*.[Pp][Nn][Gg]`}}}, []string{"PNG"}},
+		{FileFilters{{"", []string{`*.[Pp][\Nn][G\g]`}}}, []string{"PNG"}},
+		{FileFilters{{"", []string{`*.[PNG`}}}, []string{"[PNG"}},
+		{FileFilters{{"", []string{`*.]PNG`}}}, []string{"]PNG"}},
+		{FileFilters{{"", []string{`*.[[]PNG`}}}, []string{"[PNG"}},
+		{FileFilters{{"", []string{`*.[]]PNG`}}}, []string{"]PNG"}},
+		{FileFilters{{"", []string{`*.[\[]PNG`}}}, []string{"[PNG"}},
+		{FileFilters{{"", []string{`*.[\]]PNG`}}}, []string{"]PNG"}},
+	}
+	for i, tt := range tests {
+		if got := tt.data.types(); !reflect.DeepEqual(got, tt.want) {
+			t.Fatalf("FileFilters.types[%d] = %v, want %v", i, got, tt.want)
 		}
 	}
 }
diff --git a/file_test.go b/file_test.go
index 5ee972f..34a9c03 100644
--- a/file_test.go
+++ b/file_test.go
@@ -10,8 +10,8 @@ import (
 	"github.com/ncruces/zenity"
 )
 
-const defaultPath = ""
-const defaultName = ""
+const defaultPath = ``
+const defaultName = ``
 
 func ExampleSelectFile() {
 	zenity.SelectFile(
diff --git a/file_windows.go b/file_windows.go
index 4ee3478..cfbd28e 100644
--- a/file_windows.go
+++ b/file_windows.go
@@ -361,7 +361,8 @@ func initDirNameExt(filename string, name []uint16) (dir *uint16, ext *uint16) {
 	return
 }
 
-func initFilters(filters []FileFilter) []uint16 {
+func initFilters(filters FileFilters) []uint16 {
+	filters.simplify()
 	var res []uint16
 	for _, f := range filters {
 		res = append(res, utf16.Encode([]rune(f.Name))...)